ShutterstockKim Kardashian West. Mila Kunis. Angelina Jolie. Kristen Bell. What do all these famous ladies have in common? They all put the baby carriage before marriage, so to speak. This is a pretty common choice in celebrity circles—plenty of famous duos choose to have children before they tie the knot, and others still decide to co-parent without ever marrying. It's a move that was once considered taboo, unholy even...but it's quickly becoming more and more commonplace, and according to a recent sociological study, pop culture plays a major role in this shift.

Researchers from the University of Buffalo analyzed People magazine's covers to pin down a bit more information about the societal fascination with celebrity pregnancies. A trend emerged in the research: It became more and more common for celebrities to reverse the traditional order of assembling a family as time progressed, and the presentation of pregnancy-before-marriage news seemed to change as well.

“Celebrities typically did not apologize for getting pregnant outside of marriage,” study author Hanna Grol-Prokopczyk, an assistant professor of sociology, said in the study's abstract. “But the family model also changed over time. The early model dictated that you should marry by the time the baby is born. By the mid-2000s that had changed, and it became widely acceptable in the celebrity world to have a child without marrying first.”

Professor Grol-Prokopczyk became interested in the topic during her own pregnancy: She signed up for pregnancy-related news alerts, but quickly realized that the bulk of the results weren't health-related—they were about celebrity pregnancies.

“Academics often scoff at celebrity news, but in fact there’s evidence that celebrity culture is enormously influential in changing norms and has a very wide reach. For example, after Angelina Jolie wrote an op-ed after having her preventative mastectomy, a survey conducted weeks later found that 74 percent of Americans knew about her surgery and the decision," the researcher said.

Through her research, Professor Grol-Prokopczyk discovered that back in 1976, People ran a story about pregnant (and unmarried) Goldie Hawn. The caption? “She’s laughing with a baby and a new hubby on the way.”

By the mid-2000s, legally single pregnant women became mainstays on the magazine's covers, and they were most often presented as happy, socially acceptable developments.

"Real" people seem to be increasingly comfortable with welcoming babies before marriage as well. It's clearly something that's happening more and more often—and while some traditionalists are still not on board with the trend, there's no real widely-held stigma attached to this sequence of events among younger generations. What do you think—has seeing so many celebrities go the unconventional route made you feel differently about having a child before marriage?